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71.
Hsin-Yi Chang Chris Quintana Joseph Krajcik 《Journal of Science Education and Technology》2014,23(3):355-369
In this study, we investigated how students used a drawing tool to visualize their ideas of chemical reaction processes. We interviewed 30 students using thinking-aloud and retrospective methods and provided them with a drawing tool. We identified four types of connections the students made as they used the tool: drawing on existing knowledge, incorporating dynamic aspects of chemical processes, linking a visualization to the associated chemical phenomenon, and connecting between the visualization and chemistry concepts. We also compared students who were able to create dynamic visualizations with those who only created static visualizations. The results indicated a relationship between students constructing a dynamic view of chemical reaction processes and their understanding of chemical reactions. This study provides insights into the use of visualizations to support instruction and assessment to facilitate students’ integrated understanding of chemical reactions. 相似文献
72.
Schoenecker Timothy S. Martell Kathryn D. Michlitsch Joseph F. 《Research in higher education》1997,38(4):479-495
This paper focuses on the effect that diversity has on the performance and satisfaction of student groups in a computer simulation project. Using structural equation modeling, we find evidence to support the contention of previous research that diversity negatively affects group satisfaction. This finding was strongest for undergraduate groups. While the relationship between diversity and performance is inconclusive, groups that are dominated by one person tend to have below average performance. 相似文献
73.
Joseph Razek 《Journal of The Franklin Institute》1935,219(2):137-155
A simple means for combining a small direct voltage with an alternating carrier is described. This consists of connecting the direct voltage in series with an alternating voltage of the same order of magnitude. The two are then passed through a copper oxide rectifier which suppresses one part of the cycle. The degree of suppression depends upon the magnitude of the direct voltage. The resulting fluctuating voltage can be amplified to any desired degree in a conventional amplifier.The theory for the simple case of pure resistance is worked out, with an example. The solution of the more general case with inductances is indicated.The practical circuit which has been used for the amplification of thermo-couple currents, and as a galvanometer power multiplier, is shown. 相似文献
74.
Montgomery multiplication over rings 总被引:1,自引:0,他引:1
Montgomery multiplication of two elements a and b of a finite field Fq is defined as abr-1 where r is a fixed field element in . In this paper we define Montgomery multiplication of elements a(x) and b(x) in a polynomial ring modulo the ideal generated by a reducible polynomial f(x). We then show that Montgomery multiplication over a field represented by a polynomial ring modulo an irreducible pentanomial can be performed more efficiently in terms of time delay by embedding the field in a quotient of a polynomial ring modulo a reducible trinomial. The trinomial has a degree that is slightly higher than that of the pentanomial, thereby increasing the number of gates in the multiplier by a small amount. 相似文献
75.
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77.
Joseph P. Allen Meghan A. Costello Amanda F. Hellwig Corey Pettit Jessica A. Stern Bert N. Uchino 《Child development》2023,94(6):1610-1624
Adolescent success providing satisfying support in response to a close friend's call in a caregiving task was examined as a potentially fundamental developmental competence likely to predict future social functioning, adult caregiving security, and physical health. Adolescents (86 males, 98 females; 58% White, 29% African American, 8% mixed race/ethnicity, 5% other) were followed from ages 13 to 33 (1998–2021) using multiple methods and reporters. Early caregiving success was found to predict greater self- and partner-reported caregiving security, lower negativity in adult relationships, and higher adult vagal tone. Results are interpreted as advancing our understanding beyond simply recognizing that adolescent friendships have long-term import, to now identifying specific capacities within friendships that are linked to longer-term outcomes. 相似文献
78.
Joseph M. Scandura 《Journal of Experimental Education》2013,81(4):1-6
Effects of proportion of Latin suffixes and of Content Area upon newspaper article comprehension of eighth graders, as measured by cloze procedure, were investigated using a 3 x 3 factorial design. Statistically reliable mean differences were obtained between cloze test performance on Science and T. V. --Theatre passages and between such performance at High versus Medium and Low levels of Latin suffix density. The difference in mean performance across Content Areas is explained in terms of other linguistic factors-particularly differential density of prepositions. 相似文献
79.
Past research has shown that hostile schemas and adverse experiences predict the hostile attributional bias. This research proposes that seemingly nonhostile beliefs (implicit theories about the malleability of personality) may also play a role in shaping it. Study 1 meta‐analytically summarized 11 original tests of this hypothesis (N = 1,659), and showed that among diverse adolescents aged 13–16 a fixed or entity theory about personality traits predicted greater hostile attributional biases, which mediated an effect on aggressive desires. Study 2 experimentally changed adolescents' implicit theories toward a malleable or incremental view and showed a reduction in hostile intent attributions. Study 3 delivered an incremental theory intervention that reduced hostile intent attributions and aggressive desires over an 8‐month period. 相似文献
80.
Dr. Joseph J. Roy 《Clearing house (Menasha, Wis.)》2013,86(6):275-276
Teachers can help minority children close the academic achievement gap in intermediate and middle school by combining literacy instruction and content-area material. This connection improves reading achievement and increases curriculum knowledge, even if students have previously experienced difficulty with primary school reading. Fortunately, upper-elementary and middle-level learners are still naturally curious, are developing cognitively, and have acquired some basic reading skills. Teachers can therefore extend students' previous learning by using a spiral curriculum, in which curricular concepts are introduced at an appropriate level and then revisited at more challenging levels. Teachers can also increase the academic complexity for students by using strategies that include picture books, word recognition skills, intensive subject matter, vocabulary in a meaningful context, Readers Theater, and after-school activities. 相似文献